The present invention relates to a method and an apparatus for effectively cracking hydrocarbon and, in particular, to a method and an apparatus for efficiently producing a reformed hydrocarbon having a high octane number and hydrogen from a raw hydrocarbon material such as a saturated hydrocarbon, a fuel cell-mounting engine having further improved energy efficiency with using the method and the apparatus, and an energy station.
In accordance with a worldwide increase of environmental regulation, an engine using a hydrocarbon fuel has been required to save fuel consumption and lower emission of CO2 gas in recent years. A reduction in CO2 gas emission has the same meaning as an improvement in energy efficiency in combustion of hydrocarbon. A fuel cell is used for the above purpose nowadays.
The most efficient fuel for a fuel cell is hydrogen because hydrogen easily reacts on an appropriate surface of a fuel cell at a temperature higher than room temperature to produce electricity.
Since hydrogen is a gas having the smallest molecular weight, it has a problem of how to be produced, transported, and stored for a fuel cell.
Recently, a hybrid engine having a typical reciprocating engine and a secondary battery combined therewith has been put to a practical use. However, even the hybrid engine has an energy efficiency of at most 30%.
Therefore, the present invention has been made in view of the aforementioned conventional problem and aims to provide a method and an apparatus capable of efficiently producing hydrogen and producing a reformed hydrocarbon of good quality (high octane number, etc.) with suppressing carbon formation, a fuel cell-mounting engine having further improved energy efficiency with using the method and apparatus, and an energy station.
According to the present invention, there is provided a method for producing a reformed hydrocarbon and hydrogen, comprising the steps of:
subjecting a raw hydrocarbon material to thermal catalytic cracking under hydrogen for dehydrogenation to produce a reformed hydrocarbon having a degree of unsaturation higher than that of the raw hydrocarbon material and hydrogen,
introducing the reformed hydrocarbon, hydrogen and an unreacted hydrocarbon into a pressure-reducing-rising device, and
reducing and then raising a pressure to facilitate further cracking of the unreacted hydrocarbon and promote liquid-gas separation in a post-step.
According to the present invention, there is further provided an apparatus for producing a reformed hydrocarbon and hydrogen, comprising:
a reactor in which a raw hydrocarbon material is subjected to thermal catalytic cracking under hydrogen for dehydrogenation to produce a reformed hydrocarbon having a degree of unsaturation higher than that of the raw hydrocarbon material and hydrogen,
a pressure-reducing-rising device for subjecting the reformed hydrocarbon, hydrogen and unreacted hydrocarbon obtained in the reactor to pressure reduction and pressure rising, and
a separator for separating the reformed hydrocarbon, hydrogen and unreacted hydrocarbon obtained in the pressure-reducing-rising device into gas components composing hydrogen and liquid components composing a reformed hydrocarbon and the unreacted hydrocarbon by a liquid-gas separation operation.
According to the present invention, there is still further provided a fuel cell-mounting engine comprising:
a reactor in which a raw hydrocarbon material is subjected to thermal catalytic cracking under hydrogen for dehydrogenation to produce a reformed hydrocarbon having a degree of unsaturation higher than that of the raw hydrocarbon material and hydrogen,
a pressure-reducing-rising device for subjecting the reformed hydrocarbon, hydrogen and unreacted hydrocarbon obtained in the reactor to pressure reduction and pressure rising,
a separator for separating the reformed hydrocarbon, hydrogen, and unreacted hydrocarbon obtained in the pressure-reducing-rising device into gas components composing hydrogen, and liquid components composing a reformed hydrocarbon and the unreacted hydrocarbon by a liquid-gas separation operation,
a fuel cell using, as a fuel, the gas components composing hydrogen obtained from the separator, and
an engine using, as a fuel, the reformed hydrocarbon obtained from the separator.
According to the present invention, there is yet further provided an energy station comprising:
a reactor in which a raw hydrocarbon material is subjected to thermal catalytic cracking under hydrogen for dehydrogenation to produce a reformed hydrocarbon having a degree of unsaturation higher than that of the raw hydrocarbon material and hydrogen,
a pressure-reducing-rising device for subjecting the reformed hydrocarbon, hydrogen and unreacted hydrocarbon obtained in the reactor to pressure reduction and pressure rising,
a separator for separating the reformed hydrocarbon, hydrogen and unreacted hydrocarbon obtained in the pressure-reducing-rising device into gas components composing hydrogen and liquid components composing a reformed hydrocarbon and the unreacted hydrocarbon by a liquid-gas separation operation, and
a power unit for operating the pressure-reducing-rising device;
wherein the reformed hydrocarbon and the hydrogen are produced as fuels, and electric energy and thermal energy produced by the operation of the power unit are taken out with the pressure-reducing-rising device being operated by the power unit.
In the present invention, it is preferable to use a reciprocating type of a pressure-reducing-rising device.
In addition, an energy station of the present invention may further comprise a fuel cell using, as a fuel, gas components composing hydrogen obtained from the separator to take out electric energy produced by the fuel cell.